The present invention relates to a composition for use in inducing binding between parts of mineralized tissue by new formation of mineralized tissue on at least one of the parts but possibly also on the other part. The invention also relates to a process for inducing such binding, for example for the treatment of periodontitis.
The present invention relates to new biologically based techniques useful with regard to inducing binding between parts of mineralized tissue, for example teeth and bone. Even if the invention is generally applicable to provide for such binding it will, in the present disclosure, be illustrated mainly in connection with the treatment of loosening teeth, so called periodontitis. However, it should be noted that this principal illustration of the invention must not be interpreted in a limiting manner. Before the techniques of the invention are described more closely it is suitable, in order to facilitate understanding of the invention, to give a brief background to the biological conditions in connection with teeth and associated disorders. At normal dental status the teeth are anchored in special cavities, so called alveoli, in the jaw bone. Between the roots of the teeth and the jaw bone a so called periodontal membrane is located. The roots of the teeth are mainly constituted by a material called dentin. This dentin is peripherally covered by a thin layer of cementum, thickness about 0.01 to 1 mm. In this cementum inter alia collagen fibres are found which extend from the cementum through the periodontal membrane and which are anchored in the jaw bone. Thus, the cementum is extremely important for the attachment of a tooth to the jaw bone. The periodontal membrane has a thickness of about 0.2 mm and consists of the above-mentioned collagen fibres and vessels and nerves lying between said fibres and cells belonging to these tissues.
The jaw bone does not extend all the way up to the crown of the tooth, and in the part of the root which is not covered by jaw bone fibres from the root cementum extend out into the surrounding tooth gum, the gingiva. These fibres assist in anchoring the tooth and, furthermore, stabilize the tooth gum. The tooth gum, as well as the whole oral cavity, is covered by a thin layer of epithelium. This epithelium forms a dense collar or sleeve around the teeth. Adjacent to the teeth there is formed a shallow furrow between the teeth and the epithelium.
Inflammatory disorders in the tissues attaching the teeth to the jaw bone are quite frequent and strike to a varying extent the major part of the population all over the world. The methods of treatment hitherto used are mainly aiming at retarding an ongoing disease process and at preventing loosening of the teeth as far as possible. Presently, no clinically useful method exists that provides healing in such a manner as to enable the teeth to regain attachment to the jaw bone.
A further problem within this area of inflammatory disorders is constituted by congenital defects in dental attachment. Patients with such defects develop symptoms of periodontitis at an early age, so called juvenile periodontitis. Its treatment often involves extraction of the tooth and replacement with some bridge construction at a substantial cost.
The bacteria on the surface of the teeth cause chronic inflammation in the tooth gum around the teeth. Inflammatory cells excrete their enzymes intended to kill the bacteria, but which in this case also attach the collagen fibres attaching the tooth to gingiva and jaw bone. The cells on the surface of the tooth root or the cementum thus become subject to destruction, and epithelium from the oral mucous membrane grows downwardly along the teeth and produces a so called gingival crevice. In this crevice new bacteria encounter favourable growth conditions and new inflammatory cells invade this area making the decomposition of the tissues of the periodontal membrane to proceed. The cementum cells die and the bone of the alveolar area is destroyed. The process generally is a very slow one but may at intervals proceed very fast. After some time the teeth subject to attack will completely lose their attachment to the jaw bone.
Today's treatment is principally directed at removing the bacterial deposits on the tooth surfaces. When the bacteria are removed the inflammation of the gingiva and the periodontal membrane ceases and the decomposition process comes to a stop. That treatment also aims at preventing new bacterial deposits to form on the dental surface. It thus results in stopping the destruction of the attachment of the teeth to the jaw bone, but now new periodontal membrane or new cementum will be formed in the healing process.